Oil refineries include many chemical processing units, each removing one or more hydrocarbons from a mixture of many. Extensive piping runs between all of these processing units and various holding tanks. This piping is generally supported off the ground by steel racks. Each section of rack including two legs and at least one horizontal support bar is generally called a bent.
A first problem that arises with the present pipe racks is that if one of the pipes leaks liquid or gas that catches fire, an intense fire can cause the steel bent to lose its structural integrity. This will then cause the rest of the pipes on that bent to lose support, possibly rupturing the other pipes as well. This can cause a single leak to turn into a catastrophic fire and/or explosion. Thus, racks impervious to fire would avoid this problem.
Further, the location and orientation of each bent is very important to ensure the correct support of the pipe, including the correct slope to the pipe (if any). Steel bents require that the foundation of each leg be determined very accurately to ensure accurate placement of the bent. This is very time consuming, leading to greater cost and delay when building the refinery. Accordingly, a pipe rack that can be placed without such additional labor is desired.